import querystring from "querystring";
import express from "express";
import bodyParser from "body-parser";
import axios, { ResponseType } from "axios";
import { bid, ogury } from "../../src/protos/protos";

const HOSTS = {
  local: "http://127.0.0.1:8081",
  devc: "http://ms-auction-euw1a.devc.cloud.ogury.io",
  staging: "http://ms-auction-euw1a.staging.cloud.ogury.io",
  prod: "http://ms-auction-euw1a.prod.cloud.ogury.io",
};

type Transformer = {
  encode: (x) => Uint8Array;
  decode: (x) => any;
  reqType?: string;
  resType?: ResponseType;
};

const bodyTransformers: { [k: string]: Transformer } = {
  default: {
    encode: (x) => x,
    decode: (x) => x,
  },
  "/v1/hv": {
    encode: (x) => bid.BidAgentRequest.encode(x).finish(),
    decode: (x) => ogury.VastCacheResponse.decode(x),
    reqType: "application/protobuf",
    resType: "arraybuffer",
  },
};

const app = express();
app.set("etag",false);
app.use(bodyParser.json() as any);
app.use(async (req, res, next) => {
  try {
    const host = HOSTS[process.env.ENV || "devc"];
    let url = `${host}${req.path}`;
    const qs = querystring.stringify(req.query as any);
    if (qs) {
      url += `?${qs}`;
    }

    const transformer = bodyTransformers[req.path] || bodyTransformers.default;
    const reqData = transformer.encode(req.body);

    const response = await axios({
      method: req.method as any,
      url,
      data: reqData,
      headers: {
        "Content-Type": transformer.reqType || "application/json",
      },
      responseType: (transformer.resType as any) || "json",
    });

    const resData = transformer.decode(response.data);

    res.set("Content-Type", "application/json");
    res.status(response.status);
    res.send(resData);
  } catch (err: any) {
    if (!err.response) {
      next(err);
      return;
    }

    res.set("Content-Type", "application/json");
    res.status(err.response.status);
    res.send(err.response.data);
  }
});

app.listen(process.env.PORT || 8080);
console.log("Listening...");